From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9DB6C433E0 for ; Thu, 2 Jul 2020 18:30:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C88B20EDD for ; Thu, 2 Jul 2020 18:30:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbgGBSaB (ORCPT ); Thu, 2 Jul 2020 14:30:01 -0400 Received: from foss.arm.com ([217.140.110.172]:51682 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726997AbgGBSaA (ORCPT ); Thu, 2 Jul 2020 14:30:00 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2D4FA1FB; Thu, 2 Jul 2020 11:30:00 -0700 (PDT) Received: from [192.168.178.2] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1FC863F71E; Thu, 2 Jul 2020 11:29:58 -0700 (PDT) Subject: Re: [PATCH v3 6/7] sched/topology: Introduce SD metaflag for flags needing > 1 groups To: Valentin Schneider , linux-kernel@vger.kernel.org Cc: Peter Zijlstra , mingo@kernel.org, vincent.guittot@linaro.org, morten.rasmussen@arm.com References: <20200701190656.10126-1-valentin.schneider@arm.com> <20200701190656.10126-7-valentin.schneider@arm.com> From: Dietmar Eggemann Message-ID: Date: Thu, 2 Jul 2020 20:29:27 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200701190656.10126-7-valentin.schneider@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/07/2020 21:06, Valentin Schneider wrote: [...] > @@ -105,16 +122,18 @@ SD_FLAG(SD_SERIALIZE, 8, SDF_SHARED_PARENT) > * Place busy tasks earlier in the domain > * > * SHARED_CHILD: Usually set on the SMT level. Technically could be set further > - * up, but currently assumed to be set from the base domain upwards (see > - * update_top_cache_domain()). > + * up, but currently assumed to be set from the base domain > + * upwards (see update_top_cache_domain()). > */ > -SD_FLAG(SD_ASYM_PACKING, 9, SDF_SHARED_CHILD) > +SD_FLAG(SD_ASYM_PACKING, 9, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) > > /* > * Prefer to place tasks in a sibling domain > * > * Set up until domains start spanning NUMA nodes. Close to being a SHARED_CHILD > * flag, but cleared below domains with SD_ASYM_CPUCAPACITY. > + * > + * NEEDS_GROUPS: Load balancing flag. > */ > SD_FLAG(SD_PREFER_SIBLING, 10, 0) Related to my comment in [PATCH v3 5/7], maybe you wanted to add SDF_NEEDS_GROUPS for SD_PREFER_SIBLING as well ? This comment 'NEEDS_GROUPS: Load balancing flag.' makes me wondering. Currently, SD_PREFER_SIBLING isn't in SD_DEGENERATE_GROUPS_MASK=0xaef. [...]